Field of the Invention
This invention relates to an improvement in a device for detecting an end-shape of a steel tube.
As this kind of the detecting device, there has been known one as shown in FIGS. 1 and 2 of the accompanying drawings. In these figures of the drawings, a reference numeral 1 denotes one of a plurality of detectors arranged around the circumference of the steel tube as an object of detection; a numeral 2 refers to a stand, on which the detectors 1 are to be mounted; a numeral 3 refers to a steel tube; and 4 denotes a pair of pinch rollers.
In such conventional end-shape detecting device for a steel tube, when the distal end of the steel tube 3 which has been carried forward in the direction on an arrow mark by means of the pinch rollers 4 enters the stand 2 having the detectors 1 mounted thereon, the end-shape of the steel tube is detected by the detectors 1, while the steel tube 3 is being carried forward. Thereafter, the end-shape of the steel tube 3 at the rear end thereof is detected in the same manner as mentioned.
In view of the conventional end-shape detecting device of the steel tube being in such a construction as mentioned above, there have existed with the device various disadvantages such that a large number of detectors 1 need to be provided around the circumference of the steel tube 3, that the number of the detectors 1 also needs to be changed depending on variations in the diameter of the steel tube, and further that the outer circumferential surface of the steel tube between the adjacent detectors of a certain established pitch cannot be detected, because the steel tube 3 and the detectors 1 do not revolve in any manner; and various other shortcomings.